160 mil thickness, only 1 layer is needed! Other deadeners take twice as much to do the same job, at a greater cost and twice the time to install it.
For a proper installation, you must clean the surface first. This stuff is rigid when cool/cold, so you must heat it up to bend and apply it. A heat gun works great but a torch can also be used. After it cools off, it's super solid and can not be removed.